1. Field of the Invention
This invention relates to the improvement of a vehicle lamp device such as a vehicle signal lamp (e.g. a turn signal lamp or combination lamp), side marker lamp, or projector head lamp.
2. Description of the Prior Art
Heretofore, a vehicle lamp device 1 is known as shown in FIG. 18. The vehicle lamp device 1 is provided with a lamp housing 2 and a lens 3. A bulb 4 is supported by the lamp housing 2. A groove 6 for fitting the lens 3 is formed along the periphery of an opening 5 of the lamp housing 2. A fitting portion 3a of the lens 3 is fit in the groove 6. The groove 6 is provided with a hot melt material 7 as a sealing member. A lamp chamber 8 is formed between the lens 3 and the lamp housing 2.
A design for a vehicle body is diversified these days. With its diversification, a design for the vehicle lamp device 1 is regarded as important in order to improve the appearance of the vehicle. To do so, the lens 3 of the vehicle lamp device 1 is, for example, curved from the front (or rear) of the vehicle to the side thereof. In other words, in the vehicle lamp device 1 produced nowadays, the lens 3 is made larger and slenderer than is needed.
However, such a design results in an undesirable fact that an unnecessary light bundle inevitably comes out of the device 1 This light bundle makes the distinction between a luminous portion and a dark portion become unclear.
In order to solve this problem, it has been proposed that a metallic shade plate 9 be disposed between the lamp housing 2 and the lens 3 to intercept part of the unnecessary light bundle. The shade plate 9 serves to intercept part of a light bundle P emitted from the bulb 4 and clarify a border line between a luminous portion of the device 1 and a dark portion thereof. The shade plate 9 is fixed to a boss 10 of the lamp housing 2 by means of a screw 11.
However, since the shade plate 9 of the conventional vehicle lamp device 1 is fixed to the lamp housing 2 by means of the screw 11, much time is consumed in its fixation and further the number of parts are enlarged disadvantageously. In this connection, U.S. Pat. No. 4,922,398 (Date of Patent: May 1, 1990) discloses a lamp assembly in which a shade is fixed to a lamp housing with a screw.
Another conventional vehicle lamp device 1 is also known as shown in FIG. 19. The vehicle lamp device 1 in FIG. 19 includes a lens 3 made up of an outer lens 3b and an inner lens 3c. The inner lens 3c is colored and transparent. As shown in FIG. 20, the inner lens 3c serves as a reflex reflector lens. The inner lens 3c is made up of a reflex reflector lens portion 12 and a side marker portion 13. The reflex reflector lens portion 12 is made up of a number of small quadrangular pyramids. The side marker portion 13 is made up of a diffusion lens. Part of those quadrangular pyramids and diffusion lens is shown in FIG. 20.
In the vehicle lamp device 1, a light bundle P emitted from the bulb 4 is directed either directly toward the outer lens 3b and the side marker 13 each in front of the bulb 4, or indirectly toward them after the light bundle P is first reflected by a reflection surface 14. Accordingly, the light bundle P is guided in a desired direction.
The reflex reflector portion 12 of the inner lens 3c serves to reflect both a light ray incident upon the lamp housing 2 from the outside and a light bundle directed to the reflex reflector portion 12 from the lamp housing 2.
However, because the inner lens 3c is colored and transparent, it is impossible to reflect them perfectly. Especially, a light ray H' incident upon the lamp housing 2 from the outside shows a given color when the light ray H' passes through the reflex reflector portion 12. Therefore, there is a problem in that the reflection surface 14 is regarded as colored due to the light ray H'. Further, a light bundle passing through the border portion 15 between the reflex reflector portion 12 and the side marker lens portion 13 is reflected irregularly. Therefore, when the lamp device 1 is lighted, the border portion 15 becomes vague.
A construction similar to that of the vehicle lamp device 1 shown in FIG. 20 is disclosed in U.S. Pat. No. 4,912,606 entitled Vehicle Lamp Device (Date of Patent: Mar. 27, 1990, Inventor: Hiroshi Yamamoto).
In the lamp device of U.S. Pat. No. 4,912,606, a reflex reflector lens is disposed along a clear lens and part of the reflex reflector lens is provided with a side marker lens portion. However, the thus arranged lamp device still has the drawback as mentioned above.